• 약학회지
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• 제13권2_3호
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• pp.84-87
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• 1969

Microanalysis of organic sulfur compounds by means of combining thin layer chromatography and oxygen combustion flask method was attempted. The following procedure was found to be very simple and to give accurate results. The mixture of sulfa drugs was separated with T.L.C., and it was burned in a flask filled with oxygen, and the gas formed was absorbed in a dilute solution of sodium hydroxide. The solution was neuralized with hydrochloric acid and heated in a water bath. The sulfate ion formed was then treated with barium chromate solution and its absorbancy at 370 m.mu. was measured.

• The Korean Journal of Ceramics
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• 제6권2호
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• pp.172-176
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• 2000

Solid solutions of Ti$_{0.5}$Zr$_{0.5}$B$_2$were successfully synthesized and densified simultaneously from elemental reactants by the use of a field-activated, pressure-assisted synthesis method. The method involves the application of an electric current and mechanical pressure across reactant compacts to achieve combustion synthesis. Dense solid solutions with relative densities of up to 99% were produced and characterized by XRD, SEM, and EPMA methods. With a maximum measured temperature of 145$0^{\circ}C$ under a load of 86 MPa for 30 min, the desired dense solid solution wad synthesized.

• 분석과학
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• 제23권6호
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• pp.615-618
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• 2010

An oxygen bomb combustion procedure were studied for determination of heavy metal in polymer materials such as polyvinyl chloride and polypropylene by ICP-AES. This method is proposed as a rapid and simple sample preparation for decomposition of polymer containing certified contents of the analytes by teflon coated oxygen bomb combustion using different absorbing solution. The recoveries of metal were found to be 30~102% from absorbed solution by ICP-AES method using polypropylene certified reference material(PP CRM-As, Ba, Cd, Hg, Pb, Zn). The recoveries of metal using PVC CRM(Cd, Hg, Pb) was found to be 45 ~101% with same procedures.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.649-653
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• 2006

Engine Noise is composed of the mechanical and combustion noise. The contribution of combustion noise is generally bigger than the contribution of the mechanical noise at idle condition in DI diesel engine. That noise usually makes a roughness problem at the fundamental engine order. It is difficult to remove the modulation frequency so we have to directly reduce the combustion noise. The key effect of combustion noise reducing solution is the modification of the combustion pressure profile. It is accomplished by the multiple injection method and we solved the 400Hz combustion noise and improved the sound quality at idle condition in DI diesel engine.

• 한국연소학회지
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• 제18권4호
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• pp.21-28
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• 2013

HCCI engines have mainly focused on achieving low temperature combustion in order to obtain higher efficiency and lower emission. One of practical difficulties in HCCI combustion is to control the start of combustion and subsequent combustion phasing. The choice of primary reference fuels in HCCI strategy is one of various promising solutions to make HCCI combustion ignition-controlled. The behavior of ignition delay to the frequency variation of sinusoidal velocity oscillation is computationally investigated under HCCI conditions of PRF75 using a reduced chemistry in a counterflow configuration. The second-stage ignition is more delayed as the higher frequency is imposed on nozzle velocity fluctuation whereas the first-stage ignition is not much influenced.

• Korean Chemical Engineering Research
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• 제52권2호
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• pp.256-260
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• 2014

건축물 내부의 장식을 위해 사용되는 MDF합판은 화염의 착화를 지연시키기 위해 방염처리하도록 규정하고 있어 일반적으로 방염도료나 방염액 또는 방염필름 등을 적용하여 착화를 지연시키는데 이 때 적용하는 시료에 따라 방염성능과 연소 시 발생되는 가스의 유독성의 차이가 발생할 수 있어 본 연구에서는 MDF에 적용된 방염시료들의 방염성능 및 연소특성에 대해 비교분석하였으며 그 결과 방염성능에 부합하는 제품이 확인되었으나 방염처리방법에 따라 방염성능의 차이가 존재함을 확인할 수 있었으며 연소과정에서 발생되어지는 여러 종류의 유독가스의 영향도 함께 고려해야 할 요소임을 확인할 수 있었다.

• Journal of the Korean Wood Science and Technology
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• 제33권4호통권132호
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• pp.38-44
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• 2005

본 연구는 Monoammonium phosphate, Sodium borate 및 Zinc borate를 이용하여 난연성 수용액을 배합하고, 이를 이용하여 난연처리한 목재의 연소특성을 검토하기 위하여 수행하였다. 난연처리한 목재의 연소특성은 열분석(TGA, 연소열)과 난연시험(LOI, 화염전파)을 이용하여 수행하였다. 열분석과 난연시험의 결과는 다음과 같다. 1) F4로 처리한 시료가 거의 모든 연소 특성에 있어 우수한 난연효과를 나타내었다. 2) TGA curve로부터, 모든 시료는 열분해와 산화과정을 가짐을 알 수 있었다. 3) 연질목재에 대한 난연효과가 경질 목재보다 효과적이며, 난연제의 함량이 증가함에 따라 연소열은 감소하였다. 4) 난연처리된 목재의 LOI값은 24~30으로 거의 비슷하였으나 이들 값들은 비처리된 목재시료의 LOI값보다 높게 나타났다. 5) Monoammoum phosphate, Sodium borate, Zinc borate, Sodium hydroxide에 의해 배합된 수용성 난연제의 pH는 약 8.4로 옅은 암모니아 냄새가 났다.

• 한국자동차공학회논문집
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• 제12권6호
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• pp.127-134
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• 2004

Three-dimensional numerical investigations are carried out to understand the combustion characteristics inside a DLN(dry low NOx) utility gas turbine combustor during the combustion mode change period by applying transient fuel flow rates in fuel supply system as numerical boundary conditions. The numerical solution domain comprises the complex combustor liner including cooling air holes, three types of fuel nozzles, a swirl vane, and a venturi. Detailed three-dimensional flow and temperature fields before and after combustion mode changeover have been analyzed. The results may be useful for further studies on the unfavorable phenomena, such as flashback or thermal damage of combustor parts when the combustion mode changes.

• 한국화재소방학회논문지
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• 제23권5호
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• pp.66-71
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• 2009

본 연구에서는 방염처리 단청목재에 대한 방염성능 및 연소가스를 분석하여 그 독성지수에 근거한 유독성을 평가하였다. 시료에 대한 방염처리방법과 시료처리의 환경조건은 방염성능에 크게 영향을 미치지 않았다. 연소가스의 발생량은 방염액을 분무도포한 시료들에서 거의 비슷한 발생량을 보였고 독성지수는 위험등급 III에 해당하는 높은 위험도를 나타내었고, 방염액을 가압함침시킨 시료가 상대적으로 낮은 위험도인 위험등급 II를 나타내었다.

• 한국세라믹학회지
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• 제53권1호
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• pp.122-127
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• 2016

Tin oxide ($SnO_2$) nanoparticles have been synthesized by solution combustion method using citric acid as a fuel. The oxide to fuel ratio has been varied to obtain ultrafine nanoparticles with better surface area; such particles will be useful in many applications. With this synthesis method, spherical particles are formed having a particle size in the range of 11-30 nm and BET surface area of ~ $24m^2/g$. The degree of agglomeration of $SnO_2$ nanoparticles has been calculated.